Field of the Invention
The present invention relates to an attachment boss preferably applicable to a member composed of a fiber reinforced composite material, such as a fan case of an aircraft engine, and a fan case therewith.
Description of the Related Art
An aircraft engine is comprised of a fan at its foremost stage for the purpose of introducing air, peripheries of which are surrounded by a fan case. In order to reduce weight and increase strength, fiber reinforced resin (FRP) is often applied to the fan case. As FRP representatively exemplified is carbon fiber reinforced resin (CFRP), while glass fiber reinforced resin (GFRP) and Kevlar fiber reinforced resin (KFRP) can be exemplified as well.
A member of FRP is typically produced by: winding reinforcement fibers around a proper mandrel; impregnating it with thermosetting resin; and curing it by heating. FRP, where the reinforcement fibers are continuous, has an extremely high strength but, where the fibers are discontinuous, seriously loses its high strength. This causes a problem when an auxiliary device is attached to a member of FRP.
US Patent Application Publication 2008/0118683 A1 discloses a structure of a composite material having an installation flange.